Automatic louver control mechanism



Dec. 2, 1958 E. A. MADER AUTOMATIC LOUVER CONTROL MECHANISM Filed March 26, 1956 2 Sheefs-Sneet 1 FIG. Z

O a O INVENTOR E/V/L A #AMR d4 ATTORNEQJ Dec. 2, 1958 E. A. MADER AUTOMATIC LOUVER CONTROL MECHANISM 2 Sheets-Sheet 2 Filed March 26, 1956 INVENTOR [ff/L A. /7/9D i ATTORNEz Emil A. Mader, Detroit, Mich., assignor of One-half to John Spargo, Detroit, Mich.

Application March 26, 1956, Serial No. 573,759 6 Claims. (Cl. 98-116) This invention relates to louvers and particularly louvers which automatically open or close responsive to starting or stopping of air delivery to an opening'controlled by the louvers. The invention further relates to the employment of a spring serving in the absence of such air delivery to yieldably hold the louvers closed, thus resisting their rattling or vibration, and further adapted subsequent to a slight initial opening of the louvers to assisttheir full opening actuation, thus materially facilitating their response to air pressure. The invention may be regarded as an improvement upon the construction disclosed by my Patent 2,299,832 issued October 27, 1942.

An object of the invention is to provide a coiled spring.

so interconnecting an upper and a lower pivotal louver as to urge the lower louver to its closed position and the upper louver to its open position, said louvers being furthere interconnected to swing in unison, the leverage afforded such spring being so varied through pivotal travel of the louvers as to adapt the spring to resist initial opening travel of the louvers and assist their subsequent travel.

Other objects are to simplify such a spring mechanism and thus minimize the'cost thereof, to conform the spring effect more fully than heretofore to the various positions of the louvers, and to afford an improved regulation of the spring tension to suit various installations and operating conditions.

These and various other objects are attained by the construction hereinafter described and illustrated in the accompanying drawings, wherein:

Fig. 1 is a view of the inlet side of the construction with louvers closed.

Fig. 2 is a similar view of the outlet side.

Fig. 3 is a vertical sectional view of the construction, showing the closed and opened positions of the louvers respectively in full and dash lines.

Fig. 4 is an enlargement of an upper portion of Fig. 1.

In these views, the reference character 1 designates a frame of angle bar construction, forminga rectangular opening wherein a set of similar horizontally elongated louvers 2 are pivoted one above another, preferably on cylindrical pivot rods 3 occupying a common vertical plane. The latter are terminally journaled in the uprights of said frame, the upper margin of each louver being rolled snugly about the corresponding pivot rod. In the closed vertical positions of the louvers, excepting the lowermost, their lower margins overlap and seat inwardly against the top margins of adjoined underlying louvers. To assure their opening Or closing actuation in unison, the louvers are interconnected by 'a link bar 4 pivoted at 5 to brackets 6, 6a, and 6b respectively riveted or otherwise secured to the upper portions of the respective louvers on their inner faces and inwardly extending from such portions. When a blast of air is outwardly directed against the louvers, as indicated by the arrow in Fig. 3, they swing outward in unison, as shown in dash lines in Fig. 3, thus afiording escape of such air. Commonly the air blast is induced by a motor-driven fan, not shown.

United States Patent Various provisions have been made for subjecting the "ice , I z louvers to a spring or springs acting to resist initial opening travel The brackets 6a and 6b of two of the'louvers (which are preferably adjoined) rigidly carry upper and lower pins 7 and 7a similarly laterally projecting from such brackets. Such pins terminally mount a coiled spring 8, inwardly disposed from the common plane of the rods 3 and exerting an opening stress on the louvers at its;

upper end and a closing stress at its lower end. The lower mounting pin directly engages the corresponding end of 10 in its free end portion, and the spring tension holds the strip 9 and hooked lower end of the-spring in the grooves 10. This facilitates installation of the spring and permits its ready removal when desired.

The described assembly affords considerable selective.

variation of the spring tension according to the particular notch 9b receiving the spring extremity. Thus in manufacturing the described product in any certain size,"it is: not essential that the springs in each case be perfect,

duplicates, since regulation of the tension will readily compensate for minor variations in the spring characteristics. r

A vital feature of my improved spring installation is the particular location of. the pins 7 and 7a with relation to; the vertical plane determined by. the pivot axes of the louvers. In the closed position of the louvers, the upper pin is considerably closer to said plane than the" lower pin, whereby the spring exerts a considerably greater'lever age on the louvers through the lowerpin than-through; the upper one. The greater force thus transmitted through the lower pin resists opening of the louvers and avoids their rattling or vibration, when closed.

When a predetermined air pressure is interiorly applied to the louvers, the spring 8 is overcome and the louvers swing outwardly and upwardly. In so swinging, they act through the brackets 6a and 6b on the pins 7 and 7a progressively increasing the leverage exerted through the upper pin and decreasing leverage afforded by the lower pin. Since the upper pin transmits an opening effort to the louvers and the lower pin transmits a closing effort, it follows that the spring increasingly supplements air pressure, as the louvers swing open, thus assuring an ample opening travel and compensating for the progressive increase in gravitational resistance. Upon discontinuance of the air blast, the louvers gravitate, as in common practice, to their closed positions.

It will be appreciated that the described control mechanism is applicable to any arrangement of multiple louvers, and that any two of such louvers may serve as a mounting for a coiled spring.

What I claim is:

1. In a louver construction of the type comprising a frame having an air flow opening, a set of louvers extending across such opening and pivoted on the frame at axes disposed at corresponding margins of the louvers and substantially in a common plane whereby said louvers may swing inwardly or outwardly to cover or uncover said opening, and means interconnecting the louvers to effect their swinging travel in unison, such means including a link bar, a plurality of brackets respectively carried by and inwardly extending from the respective louvers, and means pivotally mounting such bar on the brackets, the combination with such louvers and brackets, of a coiled spring disposed inwardly from said common plane and subsequently assisting such travel. Thepresent invention accomplishes this result in a highly simplified manner, reducing manufacturing cost and faciliv, tating installation and tensional regulation of the spring.

and interconnecting two of said brackets, and a pair of first and second mountings for the spring ends, such mountings being respectively carried by the respective spring-connected brackets, the first mounting being disposed on' its bracket more remotely from the corresponding pivot axis than is the second mounting from its pivot axis, and the distance between the two mountings in the closed position of the louvers materially exceeding the distance from the second mounting to the pivot axis corresponding to the first mounting, thesecond mounting and the pivot axis of the corresponding louver being disposed substantially in a plane transverse to said common plane when the louvers are in closed position.

2; In a louver construction of the type comprising a frame having an air flow opening, two louvers extending across such opening, means pivoting such louvers marginally thereof-upon the frame and thus establishing pivot axes disposed substantially in a common plane and adapting the louvers to swing inwardly or outwardly t alternatively obstruct or uncover said opening,'and means interconnecting the louvers to effect their opening or closing travel in unison, the combination with said louvers, of two brackets respectively carried by and inwardly extending from the respective louvers, a coiled spring disposed inwardly from said common plane andinterconnecting the two brackets, and a pair of first and second mountings for the spring ends, such mountings being respectively carried by the respective brackets, the first mounting being disposed on its bracket more remotely from the corresponding pivot aXis than is the second mounting from its pivot axis, and the distance between the'two mountings in the closed position of the louvers materially exceeding the distance from the second mounting to the pivot axis corresponding to the first mounting, the second mounting and the pivot axis of the corresponding louver lying substantially in a plane transverse to the common plane of the pivot axes when the louvers are in closed position.

3; A louver construction as set forth in claim 1, 'said mountings being pins fixed on'and laterally projecting from said two brackets.

4. louver construction as set forth in claim 1, said spring imposing a closing effort through said second mounting on one of said two louvers and an opening effort through said first mounting on the other.

5. In a louver construction of the type comprising a frame having an air flow opening, a set of louvers extending across such opening, one above another, and pivoted at their upper margins on the frame substantially in a common plane to jointly swing inwardly or outwardly to close or uncover the opening, and means interconnecting the louvers to etfect their closing or opening travel in unison, such means including a substantially vertical link bar, a plurality of brackets respectively carried by the respective louvers upon the inner faces of their upper portions and inwardly extending from said portions, and means pivotally mounting such-bar on the brackets, the combination with said bar and brackets, of a coiled spring interconnecting two of said brackets in- Wardly of said plane, an anchorage member pivotally engaging one of said two brackets and extending into the spring and notched at points spaced longitudinally of the spring to provide selective anchorages for the spring to selectively vary its tension, one of said two brackets transmitting an opening elTort to the corresponding louver from the spring, and the other transmitting a closing effort to the corresponding louver, the mounting of the spring on one of the spring-connected brackets being so disposed on such bracket as to lie materially closer to said plane than the mounting'on the other bracket when the louvers are closed, and so that the first mentioned mounting progressively retracts from said plane and the second mentioned mounting progressively approaches said plane as the louvers swing open.

6. A louver construction as set forth in claim 2, the

' louvers being disposed one above the other, and said common plane being subsequently vertical;

2,63 2,377 Mader Mar. 24, 1953 

